A field guide to bullshit

How do people defend their beliefs in bizarre conspiracy theories or the power of crystals? Philosopher Stephen Law has tips for spotting their strategies

You describe your new book, Believing Bullshit, as a guide to avoid getting sucked into "intellectual black holes". What are they?Intellectual black holes are belief systems that draw people in and hold them captive so they become willing slaves of claptrap. Belief in homeopathy, psychic powers, alien abductions - these are examples of intellectual black holes. As you approach them, you need to be on your guard because if you get sucked in, it can be extremely difficult to think your way clear again.

But isn't one person's claptrap another's truth?There's a belief system about water to which we all sign up: it freezes at 0 °C and boils at 100 °C. We are powerfully wedded to this but that doesn't make it an intellectual black hole. That's because these beliefs are genuinely reasonable. Beliefs at the core of intellectual black holes, however, aren't reasonable. They merely appear so to those trapped inside.

You identify some strategies people use to defend black hole beliefs. Tell me about one of them - "playing the mystery card"?This involves appealing to mystery to get out of intellectual hot water when someone is, say, propounding paranormal beliefs. They might say something like: "Ah, but this is beyond the ability of science and reason to decide. You, Mr Clever Dick Scientist, are guilty of scientism, of assuming science can answer every question." This is often followed by that quote from Shakespeare's Hamlet: "There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy". When you hear that, alarm bells should go off.

But even scientists admit that they can't explain everything.There probably are questions that science cannot answer. But what some people do to protect their beliefs is to draw a veil across reality and say, "you scientists can go up to the veil and apply your empirical methods this far, but no further". Behind the veil they will put angels, aliens, psychic powers, God, ghosts and so on. Then they insist that there are special people who can see - if only dimly - through this veil. But the fact is that many of the claims made about things behind this veil have empirically observable consequences and that makes them scientifically testable.

How can science test these mysteries?Psychologist Christopher French at Goldsmiths, University of London, ran an experiment into the effects of crystals to explore claims that holding "real" crystals from a New Age shop while meditating has a powerful effect on the psyche, more so than just holding "fake" ones. But French found no difference in participants using real and fake crystals. This was good evidence that the effect people report is down to the power of suggestion, not the crystals.

Of course, this study provoked comments such as: "Not being able to prove the existence of something does not disprove its existence. Much is yet to be discovered." This is just a smokescreen. But because the mantra "it's-beyond-the-ability-of-science-to-establish..." gets repeated so often, it is effective at lulling people back to sleep - even if they have been stung into entertaining a doubt for a moment or two.

Do you think mystery has a place in science?Some things may be beyond our understanding, and sometimes it's reasonable to appeal to mystery. If you have excellent evidence that water boils at 100 °C, but on one occasion it appeared it didn't, it's reasonable to attribute that to some mysterious, unknown factor. It's also reasonable, when we have a theory that works but we don't know how it works, to say that this is currently a mystery. But the more we rely on mystery to get us out of intellectual trouble, or the more we use it as a carpet under which to sweep inconvenient facts, the more vulnerable we are to deceit, by others and by ourselves.

In your book you also talk about the "going nuclear" tactic. What is this?When someone is cornered in an argument, they may decide to get sceptical about reason. They might say: "Ah, but reason is just another faith position." I call this "going nuclear" because it lays waste to every position. It brings every belief - that milk can make you fly or that George Bush was Elvis Presley in disguise - down to the same level so they all appear equally "reasonable" or "unreasonable". Of course, you can be sure that the moment this person has left the room, they will continue to use reason to support their case if they can, and will even trust their life to reason: trusting that the brakes on their car will work or that a particular drug is going to cure them.

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